writer：Two-step method to prepare the direct Z-scheme heterojunction hierarchical flower-like Ag@AgBr/Bi2Mo
keywords：Z-scheme heterojunction; Flower-like photocatalyst; Hierarchical hollow microspheres; Visible-light response; Ag@AgBr/Bi2MoO6
source：期刊
specific source：Journal of Materials Science: Materials in Electronics
Issue time：2020年

In this study, a novel Z-scheme Ag@AgBr/Bi 2 MoO 6 heterojunction photocatalyst

was synthesized via a two-step process: the hierarchical flower-like Bi 2 MoO 6

microspheres were synthesized; Ag and AgBr were decorated to Bi 2 MoO 6

microspheres. As an environmentally friendly catalyst, it can selectively achieve the

conversion of organic pollutants without producing by-products via solar energy

irradiation. Visible light excites Bi 2 MoO 6 and AgBr nanoparticles to generate

electron-hole pairs. Due to the high conductivity of Ag nanoparticles, electrons are

conducted to AgBr via Ag nanoparticles and recombined electrostatically with hole of

AgBr, which effectively inhibits the recombination of photo-generated hole-electron

pairs. The unique electron transport path and flower-like microsphere structure allow

free radicals to fully react with organic matter. The enhanced photocatalytic

performance of the photocatalyst was evaluated by photodegradation of RB-19 under

visible light irradiation. After 120 min irradiation, the degradation rate of Ag@AgBr/Bi 2

MoO 6 to RB-19 reached 98.7%, which is much greater than the degradation

performance of AgBr/Bi 2 MoO 6 and Bi 2 MoO 6 . At the same time, after five

cycles of testing, the ternary composite still has a degradation rate of 70%. In addition,

the results of capture experiments showed that ?O 2 - and h + are the main active

substances for the decomposition of RB-19 dye molecules. The Mott-Schottky diagram

explains the band structure of the catalyst. So, this study provides a new method for

preparing Z-type photocatalysts and opens up new possibilities for selective organic

conversion.